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11.
Biochemical and thermal properties of β-galactosidase enzymes produced by artisanal yoghurt cultures
β-Galactosidases, produced by pure and mixed cultures of Streptococcus thermophilus 95/2 (St 95/2) and Lactobacillus delbrueckii ssp bulgaricus 77 (Lb 77) isolated from the Toros mountain region of Turkey, were characterised with respect to their biochemical and thermal properties. Optimum pH and temperature for maximum activity were determined and these enzymes were stable in the pH range 7–9 and in the temperature range 20–37 °C, retaining 80–90% of their initial activities. The inactivation energies of β-galactosidase from Lb 77, St 95/2 and mixed culture (Lb 77 and St 95/2) were 51.3, 44.0 and 48.3 kcal mol−1, respectively. Moreover, thermodynamic (ΔG, ΔS, ΔH) and kinetic constants (Km and Vmax) were determined and effects of metal ions were investigated. As a result, these enzymes could be considered as potential candidates for lactose hydrolysis of milk and milk products. 相似文献
12.
Food Science and Biotechnology - The main objective of this study was to examine the phenolic compounds and the antibacterial, antioxidant, anti-α-glucosidase and anti-α-amylase... 相似文献
13.
Fatma Osman Ibnouf 《Food Security》2011,3(2):215-231
This paper investigates the role of women in achieving household food security in the Western Region of Sudan, an area much
affected by the impacts of drought and civil conflicts. The study is based on a quantitative survey and qualitative focus
group discussions, supported by personal observations made during fieldwork. Additionally, the study draws upon secondary
data that is publicly available. Results demonstrate that women play a major role in producing and providing food for their
households in this high-risk climate and conflict area, while men are more likely to migrate seasonally and even permanently.
In addition, women are responsible for food preparation, processing, and food preservation and are wholly responsible for
attending to household garden plots. They therefore contribute more to household food security than men, though this contribution
is not recognized in official statistics. The study findings indicate that the main problems women face as food producers
and providers are a lack of access to the full package of improved production methods (improved seeds, fertilizers, modern
farming methods, credit services, pesticides, appropriate technologies, and marketing facilities), in addition to gender disparities
and gender-biased traditions. The impacts of natural crises and civil conflicts are gendered and therefore the responses to
these crises must be gender responsive. Holistic and strategic policies and plans that take gender issues into account are
thus needed in order to achieve food security. 相似文献
14.
The effects of various treatments and frying times on some physical, chemical, and sensorial properties of potato balls coated
with chickpea and wheat flour were studied. Potato balls were pre-dusted with chickpea flour (CF) or wheat flour (WF) as an
initial coating which was followed by dipping into 0.1% xanthum gum solution as the second coating. The last coating was breading
with 1:3 CF/WF, 1:1 CF/WF, and 3:1 CF/WF mixtures. Coated potato balls were fried at 185 °C for 5, 7, and 9 min. The pre-dusting
materials, particularly the effect of CF, enhanced yield values and sensorial properties as well as increased adhesion degree
as it decreased frying loss. Although, the breading materials raised the yield values compared to the control, the yield and
moisture content values decreased with increasing frying time. Frying loss, fat absorption, penetrometer values, and texture
values also increased. Results revealed that CF is suitable as a pre-dusting material, and 7 min was the more efficient frying
time for coated potato balls. 相似文献
15.
Fatma Bouaziz Mohamed Koubaa Khaoula Ben Jeddou Francisco J. Barba Fatma Chaari Souhail Besbes Rhoudha Ellouz Ghorbel Semia Ellouz Chaabouni 《International Journal of Food Science & Technology》2017,52(1):205-213
The aim of this work was to investigate the effect of almond gum as dietary fibre source in enhancing the wheat bread quality. Different amounts of almond gum (2%, 5% and 10% (w/w)) were used in bread formulation. The volume, texture, crust and crumb colour, as well as the sensorial properties, were evaluated and compared to control (without almond gum). The obtained results showed that almond gum addition enhanced significantly the volume of bread. The highest volume was obtained using 2% almond gum concentration with 23.6% increase, compared to control. Using almond gum in bread formulation improved considerably its texture with a notable decrease in hardness by 61.7% and 42.5% when using 2% and 5% almond gum, respectively. The sensory analysis scores showed that the better overall acceptability was found for breads supplemented with 2% almond gum, as compared to control and breads supplemented with 5% or 10% almond gum. 相似文献
16.
17.
Nanoscale crednerite (CuMnO2) was prepared in the system MnO·CuO·SiO2, using glass–ceramics technique for the first time. Based on obtained data from differential thermal analysis (DTA), the prepared samples were heat-treated at 700 and 800 °C for 2 h. The presence of crystalline phases after and before heat treatment was investigated by X-ray diffraction analysis. Crystallization of crednerite (CuMnO2), manganese silicate (Mn2SiO4) and traces of cuprite (Cu2O) and cristobalite (SiO2) phases were recognized. Transmission electron microscopy showed nanoscale crystals in the range 5–10 nm. The prepared glass–ceramics showed ferrimagnetic properties with wide range coercivity from 53 to 2217 Hci and magnetization saturation from 0.21708 to 1.2 emu/g. From IR reflection data; the reflection intensity of the light is high in the range of orange–red color and violet–blue colors and low in the range of green color. 相似文献
18.
19.
Food safety practices among pregnant women and mothers in the women, infants, and children program, Miami, Florida 总被引:1,自引:0,他引:1
Pregnant women and infants are two groups at the highest risk of severe outcomes from foodborne illnesses. We surveyed adult clients of a Women, Infants, and Children (WIC) clinic serving predominately African Americans in inner-city Miami, Florida, to assess food safety practices. Eligible and consenting women completed a 23-item self-administered survey with questions concerning food handling practices around the Partnership for Food Safety Education's Fight BAC! campaign constructs of "clean", "separate" (not cross-contaminated), "cook", and "chill". Of 342 eligible clients, 299 (87.4%) consented to participate. In general, the clients' food safety practices were most problematic in the cook and chill constructs. Using a cooking thermometer, refrigerating foods within 2 h, and thawing them safely were the least commonly reported safe practices. Women who were pregnant with their first child had the lowest food safety practice scores. Of the 62 pregnant participants, 32 (51.6%) reported eating hot dogs or deli meats without first reheating them some of the time or more often, and 22 (35.5%) reported eating soft cheeses and blue-veined cheeses some of the time or more often, putting the women at risk of listeriosis. Although all women in the WIC program could benefit from food safety education, these findings indicate that women during their first pregnancy should especially be targeted for food safety education. 相似文献
20.
In this paper, we extend the Bonferroni mean (BM) operator with the picture fuzzy numbers (PFNs) to propose novel picture fuzzy aggregation operators and demonstrate their application to multicriteria decision making (MCDM). On the basis of the algebraic operational rules of PFNs and BM, we introduce some aggregation operators: the picture fuzzy Bonferroni mean, the picture fuzzy normalized weighted Bonferroni mean, and the picture fuzzy ordered weighted Bonferroni mean. Then, a new picture fuzzy MCDM method is proposed with the help of the proposed operators. Lastly, a practical application of proposed model is given to verify the developed model and related results of the proposed model is compared with the results of the existing models to indicate its applicability. 相似文献